Cisco Systems manual MGX 8220 Shelf, Aggregation of Traffic into ATM Networks

MGX 8220 Shelf

Aggregation of Traffic into ATM Networks

Each MGX 8220 shelf connects to the BPX switch across a T3 or E3 ATM STI (Cisco Trunk Interface) to a BNI module on the BPX switch. Thus, the MGX 8220 shelf Release 3.0 supports aggregation of traffic up to 40 T1 or E1 access ports or up to 1240 64-Kbps subscribers, onto a single T3 or E3 trunk, using only a single port on the BPX switch.

In this release, the MGX 8220 shelf should normally be collocated with the BPX switch. Figure 1-2 shows how the MGX 8220 shelf usage is envisioned in Release 3.0.

Figure 1-2	MGX 8220/BPX Switch Relationship
40 T1 or E1
		MGX 8220		BPX 8620
service interface
lines
			T3 ATM STI
			connection

Broadband

ATM service

H8239

For remote locations with limited bandwidth needs, the MGX 8220 shelf can be remoted from the BPX switch using IMA trunk machines. (See Figure 1-3.)

Figure 1-3 Remote Cisco MGX 8220 Configuration

40 T1 or E1 service interface lines

	Long distance
MGX 8220		IMATM
	IMA trunk
T1 or E1 service
interface lines

BPX 8620

Broadand ATM service

H8240

The following sections provide an overview of the MGX 8220 shelf, the Release 3.0 cards, and management capabilities. In-depth details are provided in subsequent chapters.

MGX 8220 Shelf

Physically, the MGX 8220 shelf consists of cards in a 19 inch rack mountable shelf.

The shelf can be powered either from a -48VDC source or from a 220V AC source. The DC version includes DC power entry modules that can be mounted in the shelf. The AC version requires an external rack mounted AC Power Module. Both versions require a rack mounted cooling assembly. Multiple MGX 8220 shelves can be mounted in the same rack, sharing power and cooling assemblies.

The MGX 8220 shelf contains 16 slots where each slot can accommodate a front card and a back card. The front row is used for function modules, cards that perform more complex functions within the unit (for example, frame relay to ATM conversion). The back row is used for line modules, cards that provide interfaces to one or more transmission lines connected to the MGX 8220 shelf (for example, the trunk line to the BPX switch or an RS-232 line to a control terminal).

Introduction 1-3